Double action mechanism of vehicle door latch device

ABSTRACT

A door latch device has a hook lever  50  for switching a lock lever  36  residing at a locked position L to an unlocked position U when an inner open lever  29  is rotated, and a pressing spring  45  for coupling the lock lever  36  and an open link  41 . When the lock lever  36  is switched to the unlocked position U from the locked position L while an outer open lever  28  is in an actuated position Y, although the open link  41  is not displaced to an engaging position, the pressing spring  45  is compressed. The open link  41  is pushed out to the engaging position by elasticity of the pressing spring  45  when the outer open lever  28  is returned to a stand-by position X while the pressing spring  45  is compressed.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a double action mechanism of a vehicledoor latch device and particularly to the double action mechanismprovided with an anti-panic mechanism.

BACKGROUND ART OF THE INVENTION

In the conventional common vehicle door latch device, unlockingoperations by an inside lock button, a remote control transmitter andthe like are not normally completed if the outside open handle of a dooris in the state of being manipulated by an opening operation, nor is itpossible to open the door. Such a state is referred to as a panic statein the industry. If the door is getting into the panic state, theoutside open handle is made to return to a non-operation state, then theunlocking operation is made to perform by means of the remote-controltransmitter or the like again, after that, the opening operation of thedoor handle is performed again, so that the door is opened. That is, twounlocking operations and two door opening operations are required untilthe door is opened. Thus, the state, which necessitates two times ofunlocking operation and two times of door-opening operation, is definedas the panic state in the present invention.

The door latch device composed of the anti-panic mechanism, whichreduces complicated operation caused by occurrence of the panic state,is known (Japanese Utility Model Application Laid-Open No. 58-101949,and Japanese Patent Application Laid-Open No. 11-324451). The knownanti-panic mechanism is to eliminate the second unlocking operation.Even though the first unlocking operation is not completed normally bythe first door-opening operation of the outside open handle, a shiftingto the unlocked state is completed when the door handle is restored tothe non-operation state. Hence, when the second opening operation of thedoor handle is subsequently performed, it is possible to open the dooreven if the second unlocking operation is not performed.

Further, there is a conventionally known double action mechanism forshifting the latch device into the unlocked state when an inside openhandle is subjected to the opening operation under the locked state, andfor releasing the latch device when the inside open handle is subjectedto the opening operation again under the unlocked state (Japanese PatentApplication Laid-Open No. 2000-303731).

However, conventionally, a door latch device, which is provided withboth of the double action mechanism and the anti-panic mechanism, is notdeveloped.

This is not that this combination does not reside simply until now, butdifficult combination avoids practical realization. That is, the doubleaction mechanism is a mechanism related to the inside open handle, tothe contrary, the anti-panic mechanism is a mechanism related to theoutside open handle, and when combining the both simply, to become verylarge latch device that is not practical.

BRIEF SUMMARY OF THE INVENTION

Therefore, an object of the present invention is to provide a practicaldoor latch device provided with both of a double action mechanism and ananti-panic mechanism.

Further, another object of the present invention is to provide a doorlatch device with practicality in such a way as to materialize ananti-panic mechanism capable of being constituted by only components ofthe double action mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view of a door latch device of the present invention.

FIG. 2 is a cross sectional view showing a latch assembly of the doorlatch device.

FIG. 3 is a rear view showing lever group in an unlocked state.

FIG. 4 is a rear view showing lever group in a locked state.

FIG. 5 is a rear view of an outer open lever.

FIG. 6 is a rear view of an inner open lever.

FIG. 7 is a rear view of an open link.

FIG. 8 is a rear view showing relationship between the open link and aratchet pin in the locked state.

FIG. 9 is a view for explaining the double action mechanism and theanti-panic mechanism.

BEST MODE FOR CARRYING OUT THE INVENTION

A door latch device of the present invention is constituted by a latchassembly 10 mounted on a door (not shown), and a striker 11 fixed to avehicle body (not shown). The latch assembly 10 has a latch 12 which isengaged with the striker 11 when closing the door, and a ratchet 13 formaintaining engagement between the latch 12 and the striker 11. Thelatch 12 is rotatably housed within a recess part 15 formed on the frontsurface of a latch body 14 by means of a latch shaft 16 extending in aback-and-forth direction, and the ratchet 13 is rotatably housed withinthe recess part 15 by means of a ratchet shaft 17 extending in theback-and-forth direction.

The latch 12 is, in FIG. 1, urged in the clockwise direction byelasticity of the latch spring 18, and the ratchet 13 is urged in thecounterclockwise direction by elasticity of the ratchet spring 19. Thelatch 12 of FIG. 1 is in an unlatched position according to theelasticity of the latch spring 18. When the door is moved toward adoor-closed position, the striker 11 comes into contact with U-shapedgroove 20 of the latch 12 to rotate the latch 12 in counterclockwisedirection, and when the latch 12 rotates up to a half-latched position,the ratchet 13 is engaged with a first step 21 of the latch 12, so thatthe door is in a half-closed position. Further, when the latch 12reaches to a full-latched position, the ratchet 13 is engaged with asecond step 22 of the latch 12, so that the door is maintained at afull-closed position.

The ratchet 13 has a ratchet pin 24 which is projected to the rear sideof the latch body via an opening 23 of the latch body 14. On the frontsurface of the latch body 14, a metal cover plate 25 for covering therecess part 15 is fixed. The cover plate 25 is shown partially in FIG.1.

As shown in FIG. 2, on a rear surface of the latch body 14, a metal backplate 26 is fixed. The back plate 26 has a parallel plate 26A which isapproximately parallel with the cover plate 25 and is fixed to the rearsurface of the latch body 14, and a bent plate 26B which is bent toextend in the rear direction from an interior side of the parallel plate26A. To the bent plate 26B, a sub-plate 26C which is approximatelyparallel with the cover plate 25, is provided integrally or separately.

To the sub-plate 26C, an outer open lever 28 (FIG. 5) and an inner openlever 29 (FIG. 6) are pivoted by means of a mounting shaft 27 coaxialwith the ratchet shaft 17. As shown in FIG. 3, the outer open lever 28is connected to an outside open handle 30 of the door via rods, and isrotated counterclockwise from a stand-by position X to an actuatedposition Y in response to the door-opening operation of the outside openhandle 30. A bent portion 29A formed at an interior side portion of theinner open lever 29 is engageable with an end part of a relay lever 32.The relay lever 32 is pivotally mounted on the bent plate 26B andconnected to an inside open handle 31 of the door via rods and the like,by this means, the inner open lever 29 is rotated counterclockwise inresponse to the door-opening operation of the inside open handle 31.

The outer open lever 28 is urged by a returning spring 33 (FIG. 2) fromthe actuated position Y to the stand-by position X. The outer open lever28 has a bent part 35 which is engaged with an engaging slot 34 of theinner open lever 29 with a lost-motion coupling. The outer open lever isrotated counterclockwise toward the actuated position Y when the inneropen lever 29 is rotated counterclockwise according to the door-openingoperation of the inside open handle 31.

The latch assembly 10 has a lock lever 36 switching the latch assembly10 into either locked state or unlocked state. The lock lever 36 ispivotally mounted on the latch body 14 or the back plate 26 by a lockshaft 37 extending in the back-and-forth direction, and connected to aninside lock button 38 of the door. In an upper arm 39 of the lock lever36, a supporting pin 40 is provided. When the lock lever 36 is in thelocked position L as shown in FIG. 4 the supporting pin 40 is positionedat right side of the mounting shaft 27. However when the lock lever 36is switched to the unlocked position U, the supporting pin 40 isdisplaced to a coaxial position where the supporting pin 40 is alignedwith the mounting shaft 27, for this reason, the supporting pin is notshown in FIG. 3.

As shown in FIGS. 8 and 9, the supporting pin 40 is slidably engagedwith a supporting slot 42 formed on an open link 41 (FIG. 7). The openlink 41 is provided with a guide pin 44 which is slidably engaged with aguide slot 43 formed on the outer open lever 28. The open link 41 isrotated counterclockwise about the supporting pin 40 due to engagementof the guide slot 43 and the guide pin 44 when the outer open lever 28is rotated counterclockwise in response to the door-opening operation ofthe outside open handle 30 or the inside open handle 31.

A pressing spring 45 is provided between the supporting pin 40 and theopen link 41. The pressing spring 45 is mounted on a stud 46 of the openlink 41. The first leg part 45A of the pressing spring comes intocontact with the supporting pin 40, and the second leg part 45B comesinto contact with a step part 47 of the open link 41. The open link 41is urged in the leftward direction by the pressing spring 45.

A first contact part 48 is provided on an exterior side portion of theopen link 41. When the lock lever 36 is switched to the unlockedposition U from the locked position L as shown in FIG. 3, the open link41, which is pushed out in the leftward direction by the pressing spring45, is displaced into an engaging position where the first contact part48 is engageably opposed to the ratchet pin 24 in the up-and-downdirection. In this unlocked state, when the outer open lever 28 movesfrom the stand-by position X to the actuation position Y and the openlink 41 is rotated counterclockwise about the supporting pin 40 as thecenter due to engagement of the guide slot 43 and the guide pin 44, thefirst contact part 48 comes into contact with the ratchet pin 24 to movethe ratchet pin 24 downward, by this means, the ratchet 13 is separatedfrom the latch 12 so as to open the door.

When the inside lock button 38 is subjected to locking operation in thestate shown in FIG. 3, the lock lever 36 is switched to the lockedposition L from the unlocked position U, the open link 41 then movesrightward as shown in FIG. 4, and the first contact part 48 is displacedto a disengaging position where the first contact part 48 isdisengageabe with the ratchet pin 24. In this locked state, even thoughthe open link 41 is rotated counterclockwise in response to thedisplacement of the outer open lever 28 from the stand-by position X tothe actuated position Y, the ratchet pin 24 can not be moved downward,accordingly, the door is held in the opening state.

Further, a second contact part 49 is provided on the exterior sideportion of the open link 41. When the outer open lever 28 moves to theactuated position Y from the stand-by position X while the lock lever 36is in the locked position L, the second contact part 49 moves downwardin FIG. 4 and is engageably opposed to the ratchet pin 24 in theleft-and-right direction. In this state, even though the open link 41 isintended to move leftward toward the engaging position in response tothe unlocking operation of the lock lever 36, the open link 41 can notmove leftward by contact between the second contact part 49 and theratchet pin 24 as shown in FIG. 9. However, the lock lever 36 can bedisplaced to the unlocked position U by pressing the pressing spring 45.

On the inner open lever 29, an inverse L-shaped hook lever 50 ispivotally mounted by a pin 51. The hook lever 50 is provided with a hookpart 53 on the bottom thereof which is engageable with engaging pin 52mounted on the lock lever 36. In the locked state of FIG. 4, the hooklever 50 makes the lock lever 36 displace to the unlocked position U dueto contact between the hook part 53 and the engaging pin 52 when theinner open lever 29 is rotated counterclockwise by the door-openingoperation of the inside open handle 31.

Operation

(Double Action Mechanism)

In the locked state of FIG. 4, when the inner open lever 29 is rotatedcounterclockwise in response to the door-opening operation of the insideopen handle 31, the outer open lever 28 is rotated counterclockwisetoward the actuated position Y from the stand-by position X byengagement between the engaging slot 34 and the bent part 35, and theopen link 41 is rotated counterclockwise by engagement between the guidepin 44 and the guide slot 43 of the outer open lever 28. By this means,the second contact part 49 moves downward to shift to the side of theratchet pin 24, however, since the first contact part 48 does not comeinto contact with the ratchet pin 24, the door is not opened. At thesame time, the hook lever 50 moves upward in response tocounterclockwise rotation of the inner open lever 29, and the hook part53 pushes up the engaging pin 52, and the lock lever 36 is rotatedcounterclockwise toward the unlocked position U.

When the lock lever 36 starts displacement towards the unlocked positionU, the supporting pin 40 of the lock lever 36 pushes the open link 41leftward toward the engaging position from disengaging position viaelasticity of the pressing spring 45, however, as shown in FIG. 9, sincethe second contact part 49 comes into contact with the ratchet pin 24,the open link 41 can not move to the left. However, the lock lever 36 isfurther capable of counterclockwise-rotating upon compressing thepressing spring 45, as a result, as shown in FIG. 9, the lock lever 36is displaced to the unlocked position U.

When state of FIG. 9 is formed upon the door-opening operation of theinside open handle 31 in the locked state, the inside open handle 31 ismade to return to non-actuation position. Then, the outer open lever 28is made to return to the stand-by position X by elasticity of returningspring 33, then the second contact part 49 of the open link 41 movesupward than the ratchet pin 24, by this means, the open link 41 ispushed out leftward by elasticity of the pressing spring 45 to bedisplaced to the engaging position, so that the latch assembly 10becomes the unlocked state of FIG. 3. Thus, when making the door-openingoperation for the inside open handle 31 once in the locked state,although the door is not opened, the latch assembly 10 is switched tothe unlocked state from the locked state.

In the unlocked state of FIG. 3, when executing door-opening operationby the inside open handle 31 again, the outer open lever 28 is rotatedcounterclockwise, the open link 41 is then rotated counterclockwiseabout the supporting pin 40 as the center by engagement between theguide slot 43 and the guide pin 44, and the first contact part 48 of theof the open link 41 causes the ratchet pin 24 to move downward, thereby,the latch 12 is separated from the ratchet 13 so as to open the door.

According to this, the latch assembly 10 of the present invention, bythe first door-opening operation of the inside open handle 31 in thelocked state, is switched to the unlocked state, then, by the seconddoor-opening of the inside open handle 31 in the unlocked state, thelatch assembly 10 is released to carry out the door-opening of the door.This is double action mechanism.

In the above description, members constituting the double actionmechanism such as the outer open lever 28, the inner open lever 29, thelock lever 36, the open link 41, the hook lever 50 and the like, areprovided with parallel movement surface to rotational surface of thelatch 12 or the ratchet 13, accordingly, the members are mounted on rearside of the latch body 14 compactly.

(Anti-Panic Mechanism)

In the locked state of FIG. 4, when performing door-opening operation ofthe outside open handle 30, the outer open lever 28 is rotatedcounterclockwise to be displaced to the actuated position Y, the openlink 41 is then rotated counterclockwise about the supporting pin 40 asthe center by engagement between the guide slot 43 and the guide pin 44.At this time, the first contact part 48 of the open link 41 does notengage with the ratchet pin 24, thereby the opening of the door is notperformed. In the state that the outer open lever 28 is in the actuatedposition Y, when the inside lock button 38 is subjected to the unlockingoperation, the lock lever 36 starts to be displaced toward the unlockedposition U. Due to displacement of the lock lever 36, the supporting pin40 of the lock lever 36 pushes out the open link 41 leftward from thedisengaging position to the engaging position via elasticity of thepressing spring 45. However, as shown in FIG. 9, since the secondcontact part 49 comes into contact with the ratchet pin 24, the openlink 41 can not move to the left. However, the lock lever 36 is capableof further counterclockwise-rotating upon compressing the pressingspring 45 with the result that, as shown in FIG. 9, the lock lever 36 isdisplaced to the unlocked position U.

In the state of FIG. 9, when leaving grip from the outside open handle30, the outer open lever 28 is returned to the stand-by position X byelasticity of the returning spring 33, then the second contact part 49of the open link 41 moves upward than the ratchet pin 24, by this means,the open link 41 is pushed out leftward by elasticity of the pressingspring 45 to be displaced to the engaging position, so that the latchassembly 10 becomes unlocked state of FIG. 3. Accordingly, by thedoor-opening operation of the outside open handle 30, although theunlocking operation of the Inside lock button 38 is not completednormally, when the outside open handle 30 is made to return to thestand-by position X, since switching for the unlocked state is completedin such a way as to follow this, the door-opening becomes possible bythe second door-opening operation by the outside open handle 30, withoutperforming second unlocking operation by the inside lock button 38. Thusit is possible to eliminate the panic state smoothly.

EFFECT OF THE INVENTION

As described above, in the present invention, the door latch device withpracticality can be provided upon materializing the anti-panic mechanismcapable of being constituted by only components of the double actionmechanism.

1. A vehicle door latch device comprising: an outer open lever 28displaceable to an actuated position Y from a stand-by position X inresponse to an opening operation of an outside open handle 30 of a door;an inner open lever 29 arranged to displace the outer open lever 28 whenrotated by an opening operation of an inside open handle 31 of the door;a lock lever 36 for connection to an inside lock button 38 of the doorand displaceable between an unlocked position U and a locked position L;an open link 41 arranged to be displaced into an engaging position inwhich displacement of the outer open lever 28 is transmitted to aratchet pin 24 of a ratchet 13 when the lock lever 36 is in the unlockedposition U and to be displaced into a disengaging position in which thedisplacement of the outer open lever 28 is not transmitted to theratchet pin 24 of the ratchet 13 when the lock lever 36 is in the lockedposition U; a hook lever 50 provided on the inner open lever 29 forswitching the lock lever 36 residing at the locked position L to theunlocked position U in response to the rotation of the inner open lever29; and a pressing spring 45 connecting the lock lever 36 and the openlink 41; wherein when switching the lock lever 36 to the unlockedposition U from the locked position L while the outer open lever 28 isin the actuated position Y, the pressing spring 45 is compressedalthough the open link 41 is not displaced to the engagement position;wherein when the outer open lever 28 is returned to the stand-byposition X at the time of the state where the pressing spring 45 iscompressed, the open link 41 is pushed out toward the engaging positionby elasticity of the pressing spring
 45. 2. The vehicle door latchdevice according to claim 1, wherein the open link 41 has a secondcontact part 49 which restricts the displacement of the open link 41toward the engaging position by being engageably opposed to the ratchetpin 24 when the lock lever 36 is in the locked position L and the outeropen lever 28 is in the actuated position Y.